feat: establish bootable new architecture checkpoint

Replace the compressed boot path with a relocatable higher-half RISC-V entry, expand memory and SMP support, and add the driver, TTY, VFS, exec, signal, syscall, initramfs, and self-test infrastructure needed for a bootable kernel checkpoint.

1 files changed, 43 insertions, 0 deletions

diff --git a/na/fs/chardev.cc b/na/fs/chardev.cc
new file mode 100644
index 0000000..fa96276
--- /dev/null
+++ b/na/fs/chardev.cc
@@ -0,0 +1,43 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* Copyright (C) 2026 Richard Qin */
+
+/*
+ * chardev.cc — Character device registry
+ *
+ * Simple linked list of registered cdevs, searched by dev number.
+ */
+
+#include <lume/chardev.h>
+#include <lume/list.h>
+#include <lume/klog.h>
+#include <kernel/sync/spinlock.h>
+
+static list_node g_cdev_list;
+static Spinlock  g_cdev_lock;
+
+void cdev_init()
+{
+    list_init(&g_cdev_list);
+}
+
+void cdev_register(cdev* dev)
+{
+    LockGuard guard(g_cdev_lock);
+    list_init(&dev->list);
+    list_add_tail(&dev->list, &g_cdev_list);
+    printk("[cdev] registered '%s' (%d,%d)\n",
+           dev->name, MAJOR(dev->dev), MINOR(dev->dev));
+}
+
+cdev* cdev_find(uint32 dev_nr)
+{
+    LockGuard guard(g_cdev_lock);
+    list_node* pos;
+    for (pos = g_cdev_list.prev; pos != &g_cdev_list; pos = pos->prev) {
+        cdev* cd = container_of(pos, cdev, list);
+        if (cd->dev == dev_nr) {
+            return cd;
+        }
+    }
+    return nullptr;
+}